cli: Add flag for showing Clang diagnostics (#160)

Author: varungandhi-src

indexer/CliOptions.h

@@ -29,6 +29,7 @@ struct CliOptions {
   std::string temporaryOutputDir;
   std::string indexOutputPath;
   std::string statsFilePath;
+  bool showClangDiagnostics;
 
   std::chrono::seconds receiveTimeout;
   uint32_t numWorkers;

indexer/Driver.cc

@@ -118,6 +118,7 @@ struct DriverOptions {
   AbsolutePath compdbPath;
   AbsolutePath indexOutputPath;
   AbsolutePath statsFilePath;
+  bool showClangDiagnostics;
   size_t numWorkers;
   std::chrono::seconds receiveTimeout;
   bool deterministic;
@@ -134,8 +135,9 @@ struct DriverOptions {
   explicit DriverOptions(std::string driverId, const CliOptions &cliOpts)
       : workerExecutablePath(),
         projectRootPath(AbsolutePath("/"), RootKind::Project), compdbPath(),
-        indexOutputPath(), statsFilePath(), numWorkers(cliOpts.numWorkers),
-        receiveTimeout(cliOpts.receiveTimeout),
+        indexOutputPath(), statsFilePath(),
+        showClangDiagnostics(cliOpts.showClangDiagnostics),
+        numWorkers(cliOpts.numWorkers), receiveTimeout(cliOpts.receiveTimeout),
         deterministic(cliOpts.deterministic),
         preprocessorRecordHistoryFilterRegex(
             cliOpts.preprocessorRecordHistoryFilterRegex),
@@ -229,6 +231,9 @@ struct DriverOptions {
     if (!this->statsFilePath.asStringRef().empty()) {
       args.push_back("--measure-statistics");
     }
+    if (this->showClangDiagnostics) {
+      args.push_back("--show-clang-diagnostics");
+    }
     if (!this->preprocessorRecordHistoryFilterRegex.empty()) {
       args.push_back(fmt::format("--preprocessor-record-history-filter={}",
                                  this->preprocessorRecordHistoryFilterRegex));

indexer/Worker.cc

@@ -1056,13 +1056,10 @@ class IndexerFrontendActionFactory
   }
 };
 
-class IndexerDiagnosticConsumer : public clang::DiagnosticConsumer {
+class SuppressDiagnosticConsumer : public clang::DiagnosticConsumer {
 public:
   void HandleDiagnostic(clang::DiagnosticsEngine::Level,
-                        const clang::Diagnostic &) override {
-    // Just dropping all diagnostics on the floor for now.
-    // FIXME(def: surface-diagnostics)
-  }
+                        const clang::Diagnostic &) override {}
 };
 
 } // namespace
@@ -1094,6 +1091,7 @@ WorkerOptions WorkerOptions::fromCliOptions(const CliOptions &cliOptions) {
                        compdbPath,
                        indexOutputPath,
                        statsFilePath,
+                       cliOptions.showClangDiagnostics,
                        cliOptions.logLevel,
                        cliOptions.deterministic,
                        cliOptions.measureStatistics,
@@ -1199,13 +1197,15 @@ void Worker::processTranslationUnit(SemanticAnalysisJobDetails &&job,
       std::move(args), &frontendActionFactory, fileManager.get(),
       std::make_shared<clang::PCHContainerOperations>());
 
-  IndexerDiagnosticConsumer diagnosticConsumer;
-  invocation.setDiagnosticConsumer(&diagnosticConsumer);
+  SuppressDiagnosticConsumer suppressDiagnostics;
+  if (!this->options.showClangDiagnostics) {
+    invocation.setDiagnosticConsumer(&suppressDiagnostics);
+  }
 
   {
     LogTimerRAII timer(fmt::format("invocation for {}", job.command.Filename));
     bool ranSuccessfully = invocation.run();
-    (void)ranSuccessfully; // FIXME(ref: surface-diagnostics)
+    (void)ranSuccessfully;
   }
 }
 

indexer/Worker.h

@@ -59,6 +59,8 @@ struct WorkerOptions {
   StdPath indexOutputPath; // only valid if mode == Compdb
   StdPath statsFilePath;   // only valid if mode == Compdb
 
+  bool showClangDiagnostics;
+
   spdlog::level::level_enum logLevel;
   bool deterministic;
   bool measureStatistics;

indexer/main.cc

@@ -48,6 +48,11 @@ static scip_clang::CliOptions parseArguments(int argc, char *argv[]) {
     "Store temporary files under a specific directory instead of using system APIs."
     "If set, this directory will not be deleted after indexing is complete.",
     cxxopts::value<std::string>(cliOptions.temporaryOutputDir));
+  parser.add_options("")(
+    "show-clang-diagnostics",
+    "Show Clang diagnostics triggered when running semantic analysis."
+    " Useful for debugging issues related to missing headers.",
+    cxxopts::value<bool>(cliOptions.showClangDiagnostics));
   parser.add_options("")("h,help", "Show help text", cxxopts::value<bool>());
   // TODO(def: add-version): Add a --version flag
   parser.add_options("Advanced")(